Work holder with layout and checking device



Oct. 31, 1939. M YER 2,178,264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1938 4Sheets -Sheet 1 INVENTOR, IqDOLF L-NEYER ATTORNEY v 0d. 31, 1939. vALQMEY ER 2.118.264

/ WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1958 {rSheets-'Sheet 2 3.rg.3.

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14 28 By 400m L. MEYER /6 7 78 Non/ aw,

' k7 ATTORNEY Oct. 31, 1939. A. L. MEY R v 2.178.264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed llarch 30, 1938 4Sheets-Sheet 3 ATTORNEY.

Oct. 31,1939.

A. L. MEYER 2.178.264

WORK HOLDER WITH LAYOUT AND CHECKING DEVICE Filed March so, 1938 4Sheets-Shet 4 INVENTOR. 'KlaoLF L. MEYE BY Ji 24-90%) A TTORNEY Patenteda. 31, 1939 UNlTED srA'ras PATE To F c WORK HOLDER WITH I LAYOUT ANDCHECK- ING DEVICE Adolf L. MeyerrBerkeley C lif. Application March30,1938, Serial No. 198,892

6 Claims. (01. 33-114) The invention relates to a work holder arrangedfor layout and checking operations on work pieces such as stampings fromsheet material.

An object of the invention is to provide for laying out and/or checkingthe lines and points of a work piece from the dimensions on the drawingsthereof and while the piece is fixedly mounted on an adjustably mountedhead of the apparatus.

Another object is to provide an improved gaug-.

ing method wherein all measurements are set or taken in accordance withadjustments of the head which are measurable on appropriate scalesunitarily associated with it.

A further object is to provide an improved gauging device of thecharacter described wherein all correct straight lines of a mountedpiece are arranged to bedisposed in the same reference plane for theirgauging, and said reference plane may be readily established andre-established without requiring a dismounting of the piece.

An added object is to provide for working on the piece while it ismounted on the head.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth or be apparent in theFigure 6 is a fragmentary section at as in Figure 4.

Figure .7 is a section taken at 7-7 in Figure s. Figure 8 is a sectiontaken at the broken line 88 in Figure 7 Figures 9 to 12 inclusive aresomewhat diagrammatic face views showing the work piece in varioustestingpos'itions on the unit.

Essentially, the apparatus for accomplishing the present objectscomprises a surface plate on which a work-holding head is adjustablymounted for its rotativ'e adjustment about an axis having apredetermined angular relation to the reference face of the surfaceplate, and for its translation toward and from the surface plateindependently'of its rotary adjustment. Suitable scales are provided forgauging the rotary and translatory adjustments of the head which isprovided with means for effecting the fixed and adjusted mounting of awork piece upon it. The

apparatus utilizes a suitable surface gauge which is freely movable overthe face of the surface plate with the gauging arm having its point setand'maintained at a flxed distance from the surface plate whereby it isoperative in a fixed reference plane to which all point andstraight-line measurements of the mounted workpiece are re ferred bymeasured adjustments of the head, the method of use of the apparatushaving certain, marked advantages which are hereinafter brought out. 15

In the disclosed form of the apparatus for carrying out the presentinvention, a work-holding head i4 is supported from a base plate i5which has a top face portion l6 thereof accurately machined and groundor scraped as a surface plate. A standard I! extends fixedly from oneedge of the plate l5 and slidably carries a head-block element l8 whichmounts the head M for solely rotary adjustments thereof, andcomplementarily engages the standard for its guided movement in a linewhich is perpendicular to the face it. In the present instance, one sideof the standard provides mutually spaced and parallel tracks is oftrapezoidal cross-section which are ,slidably and closely engaged. withopposite side portions of a complementary slot of the block it in themanner of a dove-tail to positively and accurately guide the element inits permitted range of adjustment with respect to the face it of thesurface plate i5.

. A tongue portion N of the head-block 88 extends freely into the spacebetween the tracks i9 and threadedly receives a screw 22 which isswivelled in the standard ii for its rotation to adjust the head-blockwhile supporting the latter in its place, the axis of the screw beingperpendicular to the face I6 of the plate Hi. In the present instance,the screw 22 is swivelled in a head member 23 of the standard wherebythe head block I 8 is adjustably supported in its place by $5 the screw.An upwardly protruding screw portion carries a suitable means for use inturning the screw to'eflect adjustments of the head block; a hand crank24 is particularly shown for the purpose.

Means are provided for accurately ascertaining the amount of movement ofthe head block from an initial setting thereof, said means beingprovided as part of the standard and screw assembly. As particular] yshown, a member 25, which 23, is conically tapered above the latter andregisters with the lower end of a tubular having the scale on definesthe top of the swivelling socket for the screw and is fixed in thestandard top member member member 26 mounted on the extending screwportion below the crank 24, and the mutually adjacent parts of theexposed side faces of the members 25 and 26 are graduated in such amanner that the differences between readings for successive settingswill directly give the distance moved by the block between saidsettings. The present tool is a precision tool, and'readings of therequired degree of accuracy would be provided for, as by utilizing ascrew of relatively low pitch and one of the members 25 or 25 comprise avernier scale for use in a well-known manner.

It will now be noted that the present head I4 is disc-shaped and isfixed on a spindle 21 which extends perpendicularly to the outer face 28of the head and is arranged to Support the head for its rotation aboutthe spindle axis. Means are provided on the head for mounting a piece ofwork thereon in adjusted position opposite the face 28; as particularlyillustrated, the head I4 i provided with a series of T-slots 29 openingfrom the face 28 and arranged to receive the heads of usualclamping'screws 3|, the screws carrying nuts 32 which may'directlyengage the article to be gauged, or a carrier for the article, to fixthe work on the head. Preferably, and as shown, the slots 29 radiatefrom the head axis and aligned pairs thereof are mutually perpendicular,the specific arrangement facilitating an adjusted mounting of the workpiece on the head.

The head-carrying spindle 21 extends axially through and is journalledin a tubular casing member 33, said member being mounted on the block l8in fixed relation thereto and having one end finished to provide anannular face 34 which is perpendicular to the spindle axis for its flatengagement with the finished rear face 35 of the head, which latter faceis also perpendicular to the spindle axis. The bearings provided for thespindle are arranged to maintain the same axially centered in the casingwhile permitting the necessary slight axial movement of the head to andfrom a forcible and frictional engagement with the casing end face 34,said engagement being utilized to fix the head in rotatively adjustedrelation to the casing. The spindle and head may be provided with anaxial bore for the operation longitudinally therethrough of a usualknock-out bar (not shown) as an aid in dismounting work from the head.

As illustrated, a centrally perforated cross-wall 36 is provided at therear end of the casing 33, and is recessed from its rearward face forthe fitted reception of the outer race ring of a ringbearing assembly 31which provides the rear bearing for the spindle. The bore of the casing33 is stepped inwardly from its forward end to provide for a limiteddegree of insertion within the casing bore of the outer race ring of aringbearing assembly 38 which provides the front spindle bearing. Aflange 39 is threadedly mounted on the rear spindle portion and is fixedagainst a shoulder 4| at the forward end of the threaded spindle portionwhich mounts it by means of a lock-nut 42. The flange 39 spans thebearing 31 and has its outer portion disposed opposite the wall 36 forcontact with the wall only. when the head 14 is moved forwardly out offrictional contact with the casing face 34; in this manner, the mountedspindle is retained in the casing while the mutually opposed casing andhead faces 34 and 35 are either engaged or disengaged.

A hand-wheel nut 43 is threadedly mounted on the extreme inner end ofthe spindle 21 and is hollowed out from its forward face to span theflange member 39 and engage only the rear wall 36 of the casing, theopposed nut and wall faces being finished. A turning up of the nut 43 onthe spindle to engage it with the wall 36 is arranged to effect aforcible engagement of the head l4 against relative rotation withrespect to the casing, and so lock the head in rotatively adjustedposition on the casing. A subsequent backing off of the nut 43 willrelease the head for its rotative adjustment, the required amount ofturning of the nut for releasing the clamped head being obviouslyslight.

An arcuate scale plate 44 is fixed on the casing 33 to extend radiallybeyond the periphery of the circular head l4, and carries verniergraduations 45 extending from a central zero point and for use withangle graduations 46 extending on and around the peripheral edge of thehead whereby to provide for predetermined rotary adjustments of the headabout its axis or to ascertain angular relations of a work piece. Tofacilitate angle readings and settings, the zero of the graduations 45may be provided at a point which lies in a plane which includes thespindle axis and is perpendicular to the reference face I6 of thesurface plate I5. Also, the zero of the angle scale on the head ispreferably provided at a point which lies in a plane including thespindle axis and the longitudinal center line of a T- slot 29.

-Means are preferably provided for effecting a controlled rotativeadjustment of the head l4 about its axis for angle-setting purposes,said means essentially comprising a gear drive which is optionallyoperative against the spindle 21. As shown, a shaft 41 is journalled inthe casing 33 intermediately of its length and to extend perpendicularlyof the spindle axis in non-intersecting relation to said axis. The shaft41 carries a worm gear 48 fixed operative in the casing cavity and in atangential direction against the teeth of a complementary spur gear 49which is mounted on the spindleifl for its normally free rotation aboutthe spindle, the gear 49 being disposed adjacent a rearwardly extendingshoulder of the spindle adjacent the forward end of the casing cavity.One end of the shaft 41 extends externally from the casing and carriesmeans for manually effecting its rotation, the latter means being shownas comprising a hand crank 5i.

A clutch means is provided for causing the gear 49 to rotate with thespindle whereby an actuation of the hand crank 5| may controlledlyrotate the spindle and head as desired. As particularly shown, a sleevemember 52 is mounted on the spindle between the gear 49 and the rearcasing wall 36, and is splined to the spindle for its rotation therewithand its adjustment .along it. A socket 53 is provided in the rear faceof the gear 49 for receiving a pin 54 which extends forwardly from thesleeve 52 at the same radial distance from the spindle axis, and anhelical compression spring 55 is constantly operative between the rearsleeves end and the wall 36 to urge the sleeve toward the gear to engageand yieldingly maintain the pin in the socket so that the manuallyrotated gear may rotate the spindle and head when the pin engages thesocket.

Since the rotary adjustment for the head by means of the worm gearing isrelatively slow, the described clutch arrangement is normallyheldinoperative by a screw 56 threadedly engaged in and through the sidewall of the casing 33 and releasably engaging the sleeve in a manner todispose the pin 54 rearwardly of the socket '63. As shown, the inner endof the screw 56 -is conically tapered and is arranged for its wedgingengagement with the forward side of a complementary conical flange 51provided on the sleeve and having its apex forwardly. As the screw 56 isturned in, it is arranged to force the sleeve rearwardly against theresistance of the spring- 55 to disengage the pin 54 from the socket 53and so render the .worm gearing ineffective as an adjusting means forthe head; when the head, having been freed for its rotary adjustment byloosening'the hand nut 43, is set approximately, the clutch controlscrew 56 is backed out of its engagement with the flange 51 to permitthe clutch engagement, and the crank may then be operated to completethe with precision. The head of preferably knurled or otherwise formedto facilitate a manual manipulation of the screw.

It will now be noted that the head block 18 comprises an inner portion58 providing the tongue l8 engaged by the 'screw 22 and the groove whichreceives the tracks 19, a bracket-arm portion 59 extending from theportion 58 at the lower part thereof, and an upstanding ear 6| at theend of the arm 59. The oposed faces of the' portions 58 and SI aremutually parallel in planes perpendicular to the surface plate face l6,and a bolt 62'extends through the ear 6i and the headcarrying casing 33into the block portion 58as a means to mount the casing on the bracketprovided by the block, the axis ofsaid bolt being parallel to the fronthead face l6.

Mutually aligned bosses 63 provide the end portions of thehead-receivlng bore of the casing 33, the end faces of the bosses beingmutually parallel and so spaced as to provide for their simultaneousfitted engagement against the opposed faces of the block portions 58 andSi when the bolt 62 is installed. The bolt-receivthe screw 56 is ingbores of the ear SI and of the casing 33 are smooth, and the boltportion thereat may be unthreaded for its snug centering fit therein.The inner bolt end is threaded and engages a threaded bore in the blockportion 58 whereby a tightening of the bolt against the ear 6! may clampthe boss portion of the casing 33 between the portions 58 and ti tofrictionally secure the casing against rotation about the bolt axis;this arrangement permits a rotativelyset adjustment of the working headIt with respect to the plane of the surface plate l5.

Arms 66 are fixedly mounted on the casing 33 at opposite sides thereofand extend laterally thereof beyond the head il and into the generalplane of the head disc. At its outer end, each arm 56 has a relativelysmall transversely directed projection 65 having its free end face 68coplanar with the axis of the head it and providing a reference facewhich is arranged to be parallel to the gauging face it of the surfaceplate when the head axis is parallel to the latter face. The referencefaces 86 of the difierent arms 66 are oppositely directed,'mlght beprovided on the same supporting arm, and are provided-for use -with asurface gauge supported on the face iii in certain gauging operationshereinafter described.

angular setting The surface'gauge which is provided and utilized for thepresent purposes may be of any suitable type or structure for engagingthe work asrequired while providing the desired degree of gaugingaccuracy. The illustrated surface gauge 61 is of the dial indicator typewherein the indicator 68 is adjustably mounted on a stem 69 whichextends from a base 1| arranged for supported movement on and along thetop face 16 of the surface plate i5. An arm .12 extends from theindicator for the engagement of its free point 13 with either referenceface 66 and with correspondingly directed points and surfaces to bechecked for determining indicator readings.

The gauging of an article or work piece 15 is particularly shown forillustrating the method of use of the present apparatus, said articlecomprising a machine partwhich is shaped .and

stamped from sheet material and being flat except for a flat lug part 16which extends transversely from the rest of the'piece, and presents aflat stop face 16'. A circular hole 11 which extends transverselythrough the piece 15 is utilized inmounting the piece 15 on the head 14by driving a slightly tapered pin 18 into the hole 11 to mount the pieceon the pin, fixing the pin in a V-block clamp 19, and mounting the clampon the head with the pin perpendicular to the head face 28 by the use ofone or more screws 3|; as shown,- but one clamp screw is utilizedto'secure the present work holding clamp 19. It will be understood thatthe hole 11 may be arequired one in the piece, or may be one which isprovided especially for mounting the piece in a work holder of the typeshown.

It will now be noted that the piece 15 has several formal features anddimensions which must be adhered to with precision in the'flnishedmanufactured article. For instance, the piece is provided with aninterior pin-guiding slot of uni form width having a straight portionBland an arcuate portion 82 in definite relation to the axis of the hole11, and the lug 16 has a definite position in the piece, all asexemplified in Figure 2' which presents the draftmans drawing for the ofpresent interest shown.

By reference to Figure 2, itwill be noted that all of thegivendimensions are measured from perpendicularly related reference lines:r-a: and 11-11, which lines intersect at the center C for the. hole 11,and that slot portion 86 are parallel .to. the line .r .r at distances aand b from it. The end lines of the slot Sl-BZ are semicircles havingtheir radii r equal to half of the slot width and having their centersat measured mstances from the lines :c :r and 11-11; the'arc at the endof the slot nearest the point C is a distance 0 from the line :r:c and adistance d from the line 11y, while the center for the other slot end isa distance 6 from the line :c-.r and a distance I from he line y-1 Thecenter of curvature P for the curved sides of the arcuate slot portion82 lies at the distance d from the line z/y and at a distance 9 from theline 2-1:; accordingly, the radius of curvature for the arcuateslot sidenearest the center P equals the distance 9 minus r (gr), while theradius of the opposite slot side equals g plus r (g+r). In the presentpiece 15, the stop face 16' of the outturned lug 16 is arranged to bependicular to the rest of the piece and to include the axis of the hole11 in its plane and to make a definite angle A with the reference line31-11,

as shown, the center for of the clamp the sides of the straight 4- ablank being suitably marked as at m to indicate the proper inside bendline for the lug. The outlines of the piece are also delineated inFigure 2, the dimensions and measurements thereof being omitted in thepresent instance for simplifying the showing.

As is particularly'illustrated in Figures 1, 3, 4, 9, 10 and 11, thepiece 15 is shown as being so positioned on the head that the axis ofthe hole 11 coincides with the spindle axis. This mounted disposal ofthe piece may be readily eflected by setting the head 14. at aconvenient and fixed height with its axis parallel to the top face 16 ofthe surface plate l5 and with the slot 29 which receives the clamp screw31 vertical for a zero reading on the head scale. Since the onlyrequirement for the initial height setting of the head is thatsubsequent height adjustments required for gauging be permitted, thehead may be conveniently disposed for a whole number reading on theheight scale. The point 13 of the surface gauge 61 may then be appliedto the top or bottom side of the pin 18 for setting the point height,the head I4 is then rotated through an angle of ninety degrees, and theset point 13 is again and similarly applied to the pin; if the indicatorreadings are the same (preferably zero) for both applications of thepoint 13 to the pin 18, the latter is properly centered, otherwise, an

adjustment of the work-mounting member 19 is made until said readingsare equal.

When the mounting pin 18 has been centered as described, the point 13 ofthe surface gauge 61 is set for its movement in a reference plane at thedistance of the spindle axis from the surface l5 by adjusting it for azero reading of the indicator when it engages the upwardly directedreference point 66. The head is then lowered the distance a, the pin 18is loosened for its centered rotation in the member 19, and the piece 15thereon is rotated about the head axis to a position wherein thestraight slot edge portion to whichthe measurement 11 applies isdisposed for the application of the set gauge point 13 to it from aboveand for a uniform reading of the indicator as the point 13 is movedalong its length, whereby the slot edge may be parallel to the referenceplane in which the set point 13 is movable. If the indicator reading isthe same as when the gauge point was originally set, the tested edge isalso correctly spaced from the axis a:--.'r. The aforesaid completedsetting of the piece with respect to the head is thereafter maintainedby tightening the grip of the work holder on the pin 18 and is thatspecifically shown in Figure 9. It will be understood that otherstraight edges of the piece may be similarly tested with the gauge point13 having been initially set against a correspondingly directedreference face 68 when the piece was at its initial level.

For checking the distances of the ends of the ends of the slot 81-82from the line y-y, the head H is rotated through ninety degrees from itsFigure 9 position to correspondingly rotate the work piece, the headangle scale 46 being utilized for measuring the angle. As shown inFigure 10, the set gauge point 13 is applied for checking the distanceof the end of the slot nearest the pin 18 from the pin, and the head hasaccordingly been lowered a distance of (1 minus 1' (d-r) whereby thepoint to be checked presumably lies in the reference plane of the point13 and will be correct only if the indicator reading is zero as when thepoint was originally set at the reference point 63.. The other slot endmay be similarly checked tight in this setting.

by turning the piece downwardly instead of upwardly, the head beinglowered a distance of j plus r (f+1'). It will be understood that otherpoints of the work piece may be similarly checked with respect to eitherof the lines :c-a: or 11-41. 5 The angular relation of straight lines ofthe tested piece to other lines of the piece or to the lines z-a: or y-ymay be tested by comparing readings on the head scale when the differentlines at interest are disposed in the common ref- 10 erence plane of thegauge point 13. As is shown in Figure 11, the head has been rotated in aclockwise direction from its initial position of Figure 9 through anangle of ninety degrees plus the angle A (90+A) to presumably bring the15 lug face 16 into the reference plane. Checking is effected in thisinstance by applying the point 13 both along and across the face 16',whereby to ascertain as to whether the'face is truly perpendicular tothe plane of the rest of the piece 29 and includes the pin axis,provided the angle is correct.

Figure 12 shows the piece disposed on the head for using the gauge point13 for checking the accuracy of the arcuately curved inner edge of the 5slot 8l--82. For performing this operation, the piece is reset on thehead so as to bring the center P into the axial line of the head I4, thepin 18 being shifted away from said center by the direct distance from Bto C, which distance is readily so determined by measurement orcomputation in the original scale drawing. With the head It lowered forthe distance g minus 1 (9-4) and the pin 18 loosened for its rotation,the piece is swung about the pin to dispose the gauge point 13 35against the slot edge being tested and is clamped I A subsequent rockingof the head about its axis to move the curved edge beneath the point 13will provide thedesired test for the correctness of curvature. Thissetting is 4.0 understood to provide for checking all arcs having P asthe center. Also, it will be noted that the circular edge portioncentering about the pin 18 may be tested for accuracy of curvature whenthe piece is mounted as in Figures 9 to 11 sim- 4,5 ply by rocking saidedge portion beneath and in contact with the gauge point 13.

It will be noted that the foregoing applications of the presentapparatus for testing and checking are illustrative of but a few of theoperations 50 which may be devised and performed by a mechanic. Also,the piece being tested may be a pattern, a partly finished article, or acompleted article. If the surface gauge used provides a scribing point,a scribed outline may be checked 55 or produced on a blank if desired,all solely by' the described use of the head scale and the elevatorscale and the reference point 66 in mutual cooperation. Furthermore, thedescribed provision and measuring use of the relatively large 00 headand elevator scales in lieu of the relatively small scales of a surfacegauge are understood to provide a degree of checking precision notobtainable with the gauge scale.

While the indicated use of the reference point 55 65 to establish areference plane for gauging operations is generally feasible only whenthe spindle axis is parallel to the surfaceplate face 16, the permittedangular adjustment of the head assembly about the axis of the bolt 62may pro- 70 vide for the disposition of bevelled faces for their testingwith the surface gauge in the described manner.

If desired, a rotary power tool 85 may be mounted on the base plate 15for the application of a drill or reamer or grinder or other rotary toolto a work piece mounted on the head 14, this being of marked value sinceit permits correctzing a pattern, or a presumably finished piece, 5without having to release it from the head for tool unit is preferablyheld against lateral shifting over the plate face l6; as by dowel pinsextending downwardly from the base of the assembly 81 and into sockets88 provided in the plate I5.

From the foregoing description taken in connection with the accompanyingdrawings, the ad- 'vantages of the construction and method of operationwill be readily understood by those skilled in the art to whichtheinvention appertains. While I have now described the features andprin- 3 ciples of operation of a structure which I now consider to be apreferred embodiment of my invention, I desire to have it understoodthat the showing is primarily illustrative, and that such changes may bemade, as desired, as fall within the scope, of the following claims.-

1. A work holding and checking device comprising a base providing anupwardly facing and plane reference surface, a'head block mounted onsaid base for rectilinear adjustment with respect to said base surface,a Work holding head mounted on said block for rotary adjustment with respect to an axis parallel to said reference surface,

and means providing a reference point on the.

block, said point comprising a flat area parallel to said base surfacefor reference engagement by the gauging point of a surface gaugestanding on. the base surface.

2. A work holding and checking device comprising a base providing anupwardly facing and plane reference surface, a head block mounted on thesaid base for rectilinear adjustment with re spectto said base surface,a work holding head mounted on said block forv rotary adjustment withrespect to an axis parallel to said' reference surface, and meansproviding reference points on the b ock, said points comprising mutuallycoplanar fiat areas parallel to said base surface for referenceengagement by the gauging point of a surface gauge standing on the basesurface.

3. A work holding and checking device com: prising a base providing anupwardly facing and plane reference surface, ahead block mounted on thesaid base for rectilinear adjustment with respect to said base surface,a work holding head mounted on said block for rotary adjustment withrespect to an axis parallel to said reference surface, and meansproviding a reference point disposed on the block adjacent the peripheryof said work holding head, said point beingarranged for referenceengagement by the gauging point of a surface gauge standing on the basesurface.

4. A work holding and checking device comprising a base providing anupwardly facing and plane reference surface, a head block mounted onsaid base for rectilinear adjustment with respect to said base surface,a work holding head mounted on said block for rotary adjustment withrespect to an axis parallel to said reference surface, and meansproviding a reference point on the block disposed in a plane includingthe axis of rotation of the head and parallel to the reference surfaceof the base, said point being arrangedfor reference engagement by thegauging point of a surface gauge standing on the base surface.

5. A work holding and checking device comprising a base providing anupwardly facing and plane reference surface, a head block mounted on thesaid base for rectilinear. adjustment with respect to said' basesurface, a work holding head mounted on said block for rotary adjustmentwith respect to an axis parallel to said reference sur-.

face, and means providing a reference point on the block laterally ofthe head, said reference point being disposed in a plane including theaxis of rotation of the head and parallel to the ref- .erence surface ofthe base and being arranged for reference engagement by the gaugingpointof a surface gauge standing on the base surface.

6. A work holding and checking device comprising a base providing anupwardly facing and plan-e reference surface, a head block mounted onsaid base for rectilinear adjustment with respect to said base surface,a work holding head mounted on said block for rotary adjustment withrespect to an axis parallel to said reference surface, and oppositelydirected reference faces'provided on the block, said faces beingarranged for reference engagement by the gauging p bint of a surfacegauge standing on the base surface.

ADOLF L. mm.

